The preliminary experimentation has been carried out in vitro, using primary cultures of fetal and adult human RPE cells, or murine macrophages, as well as commercial cell lines of human RPE (ARPE-19), murine microglia (BV-2) and human monocytes (THP-1). Preliminary collected data: - In line with published data, stimulated human RPE cell line, ARPE-19, were found to form inflammasomes, that produced caspase-1 and the physiologically active IL-1beta and IL-18. - Stimulated adult human RPE lines also formed inflammasomes, but their levels of the specific cytokines were lower than those of the ARPE-19 line. - Unlike adult human RPE lines, fetal human RPE cell lines failed to similarly respond, as shown by absence of the specific cytokine production. - BV-2, a cell line of murine microglia, responded well to stimulation by the remarkable production of caspase-1, IL-1beta and IL-18. - Cultures of murine macrophages or a line of human monocytes (THP-1) produced considerably higher levels of all tested inflammasome products than did ocular-related culture cells. - Stimuli used for activation of the tested cell cultures included lipopolysaccharide (LPS), IL-1alpha, silica and, importantly, a component of drusen, 7-Ketocholesterol (IOVS, 2010, 51:4942)(a gift from Dr. Ignacio Rodriguez). Another component of this project, to be initiated shortly, would deal with the inflammasome formation and specific cytokine production by stem cells collected at different stages of the induced process of the cells acquisition of RPE features. This study is to be carried out in collaboration with Dr. Kapil Bharti in whose lab the stem cells are being induced to undergo the phenotype change.